Why do many people believe that Abdullah ibn Saba formed Shi'ism, and how can we refute it?

Abdullah b. SabaSunni-Shi'a
Why do many people believe that Abdullah ibn Saba formed Shi'ism, and how can we refute it?
Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answer updated 4 years ago

Those who claim any relationship between Shia Islam and a person named
as Abdullah Ibn Saba’ are repeating a fabricated lie which was created
by the enemies of Shia Islam as a part of their fake propagation
against Shia Muslims. Such claim is like the claim of some enemies of
Islam that the religion of Islam was created by idol worshippers. It
is very simple to know that these claims have no scientific value at
all as Islam is the religion which is very clearly against idol
worship and it considers it as the most dangerous major sin.

Abdullah Ibn Saba’ is a person who is being mentioned in our Shia
books as a cursed person and never as a narrator in any narration that
we consider or follow. So how can a person who is cursed in all our
books be the source of our faith. Many of our and Sunni scholars
believe that Abdullah Ibn Saba’ is a fabricated name created by a well
known liar Saif bin Omar because they found that all the stories re
Abdullah Ibn Saba’ were by one person only who is Saif bin Omar. Many
books have been written by Sunni and Shia proving that this name is
fabricated by Saif bin Omar, the famous liar who fabricated names of
many persons who did not even exist. Some of them were mentioned in a
book called 150 Fabricated Companions where the author Allamah
Murtadha al-Askari proved that at least 150 companions mentioned in
some books never existed and the only person who created their names
is Saif bin Omar. So if Abdullah Ibn Saba’ did exist, all our books
curse him. And if he did not exist, the whole lies are disclosed.

Shia Islam is the real Islam preached and practised by the Holy
Prophet (SAWA) himself and his holy progeny, the Ahlul Bayt (AS) and
every matter in Shia Islam is fully supported by evidence from the
Holy Qu’ran and authentic Sunnah.

These allegations add more evidence that the opponents of Shia Islam
have no evidence at all against Shia Muslims. That is why they create
fake allegations to mislead lay people but they forget that the truth
or the falsehood will be disclosed sooner or later and the truth will
always prevail.

Founder of Shia Islam:

The Prophet Muhammad (SAWA) was the founder of Shia Islam being the real Islam.

Shia in Arabic language means the followers, but it is used in Islamic history as a term specifically for the followers of Imam Ali (AS) who believed in the fact that He is the legitimate successor of the Prophet Mohammad (SAWA).

Shia in Qur’an:

In Qur’an Allah (SWT) has given this name of Shia to His great prophet Ebraheem (Abraham) (AS) as a follower of Noah (AS) ( Surah Saffaat:83).

Follower of prophet Musa (Moses) (AS) was called in Qur’an as: from His Shia (Surah Qasas:15).

Shia in Hadeeths:

The name of Shia was given by the Prophet Mohammad (SAWA) to the most sincere Muslims, those who were close to Imam Ali (AS).

There is an authentic Hadeeths stating that (Ali and His Shia will be the winners) which was narrated in many Sunni books e.g. :

Al-Manaaqib by al-Khawaarizmi, chapter 17, second Hadeeth, narrating from Abu Sa'eed al-Khidri .

Al-Hafiz Abu Na'eem in Hilyat al-Awliyaa' narrating from Ibn Abbas.

Jalaluddin al-Soyouti in his Tafseer al-Durr al-Manthour, narrated from Ibn Asaakir and Jabir ibn Abdullah al-Ansaari.

Ibn Hajar in Al-Sawaaeq al-Muhreqah, Volume 11, page 122.

Kifaayat al-Taalib, by al-Kanji al-Shaafe'ee, Volume 62.

There is another authentic Hadeeth stating that the Prophet Mohammad (SAWA) said (The Shia of Ali will be the winners) which was narrated by Anas Bin Malik and mentioned in Yanaabee' al-Mowaddah by al-Qandoozi al-Hanafi page 180 ,and Konooz al-Haqaa'eq page 88 and Entihaa' al- Afhaam page 222.

Abu Huraira has narrated that the Prophet Mohammad (SAWA) told Ali: (You will be with me and your Shia will be in Paradise). This Hadeeth is mentioned in Tafseer al-Durr al-Manthoor by Jalauddin al-Soyouti, volume 6, page 379. And in Yanaabee' al-Mawaddah by al-Qandoozi al-Hanafi, page182 and many other Sunni books.

Al-Khateeb al-Baghdadi narrated in his famous book Taareekh Baghdad, that the Prophet (SAWA) told Ali: Oh Ali, You and your Shia will be in Paradise. (Tareekh Baghdad, Volume 12, page 289).

Muslim scholars confirmations:

Ibn Khaldoon wrote in his book of history (Taareekh Ibn Khaldoon: 3:364): A group from the Sahaba were following Ali and they believed that Ali is more entitled to lead the Ummah than anyone else after the Prophet (Shaikh Subhi al-Salih in al-Nodhum at-Islamiyah page 96 and Mohammad Ali Kurd in Khitat al-Sham Volume 5 page 251) and many other Sunni scholars confirmed that the Shia existed from the time of the Prophet (SAWA).
Wassalaam.